Abstract: The scattering behavior of ultrasonic waves in inner obstacle of solid may be observed by the means of dynamic photo elasticity technique, and this will help us to understand the scattering characteristic. We found out ultrasonic receiving wave the integral path by observe transmitting signal of ultrasonic phased array. Then, validating the method using IIW test block, 22 signals A-scan are focused in crack and boundary of specimen, point by point scanning, added signals were different, so gray was different, achieving B-scan imaging, proving the method was available.